Need to build Dummy proof precharge circuit for 144v build

[steveo]

Hey Everyone,

I'm looking for some simple & easy ways to build a idiot proof precharge circuit for my 144v controller

Presently i use a circuit breaker on the positive side of the power cable between the battery positive & controller positive. To pre-charge i have a 5w 1k resistor with a momentary switch attached to both ends of the breaker. So to precharge i hold the momentary switch for a second or 2 & then turn on the circuit breaker to run the controller.

any more creative ideas out there?

-steveo

 

[wshi]

This might help: http://www.diyelectriccar.com/forums/showthread.php/precharge-why-do-need-do-do-25419.html

 

[fechter]

Any reason why you can't just leave the resistor on all the time? That seems pretty effective.

A real idiot resistant design is not so easy.

I worked on one for quite a while, but it became too complex.
One of the simpler versions of it uses a main contactor relay and the relay coil is driven off the controller power inputs. This way if the controller fails to precharge, the relay can't close (like if the controller was shorted). The capacitors in the controller have enough juice to energize the relay.

It would be nice if the relay can't close until the controller voltage nearly matches the battery voltage, then closes automatically so you only have one switch to deal with.

 

[northernmike]

2 position keyswitch w/555 timer delay, somehow?

 

[steveo]

Any reason why you can't just leave the resistor on all the time? That seems pretty effective.

A real idiot resistant design is not so easy.

I worked on one for quite a while, but it became too complex.
One of the simpler versions of it uses a main contactor relay and the relay coil is driven off the controller power inputs. This way if the controller fails to precharge, the relay can't close (like if the controller was shorted). The capacitors in the controller have enough juice to energize the relay.

It would be nice if the relay can't close until the controller voltage nearly matches the battery voltage, then closes automatically so you only have one switch to deal with.

Hey Fechter ..

thats a great idea..and really easy .... i think i'll be doing that


-steveo